Recently, Mother Manning & I have been shopping for recruitment outfits for the fall. One of our outfits includes a white blouse. Our VP of recruitment included the words 'button down' in her email to describe the shirt she wanted.

This sparked some conversation between mom & I. The differences between a button down, button up & blouse.

To me, there was no difference between a button up and a button down (I now realize that yes, there is indeed a difference!). I would have considered a button down to be the pink or blue shirt above. I consider the purple top to be the only blouse in the arrangement.

Mother Manning on the other hand, see the pink top as a button down (the collar buttons down), the blue as a button up or blouse and the purple as a blouse.

I think the best classifications are a combination between our two difference definitions. Here's what I came up with:
Pink: button down
Purple: blouse
Blue: button up or blouse (I would say buttoned blouse)